U.S. patent number 5,176,258 [Application Number 07/679,902] was granted by the patent office on 1993-01-05 for sealed package and method for sealing products in a package.
This patent grant is currently assigned to Linvatec Corporation. Invention is credited to John L. Antal.
United States Patent |
5,176,258 |
Antal |
January 5, 1993 |
**Please see images for:
( Certificate of Correction ) ** |
Sealed package and method for sealing products in a package
Abstract
A package includes a peripheral flange around a blister defining
an open cavity for receiving a product and a compressible insert
for securing the product against movement in the cavity. At least
one projection on the insert extends laterally from the cavity over
the peripheral flange, and a lid covering the cavity is
continuously sealed to the peripheral flange and the projection
along a single seal. A method for sealing products in the package
includes supporting the peripheral flange on a rigid support
surface, and compressing the lid against the peripheral flange with
heat and pressure to compress the projection between the lid and
the peripheral flange and heat seal the projection to the lid
simultaneously with sealing of the lid to the peripheral flange
along the peripheral seal.
Inventors: |
Antal; John L. (Palm Harbor,
FL) |
Assignee: |
Linvatec Corporation (Largo,
FL)
|
Family
ID: |
24728859 |
Appl.
No.: |
07/679,902 |
Filed: |
April 3, 1991 |
Current U.S.
Class: |
206/461; 206/438;
206/471; 206/523 |
Current CPC
Class: |
B65D
75/326 (20130101); B65D 75/36 (20130101); B65D
2575/3245 (20130101) |
Current International
Class: |
B65D
75/28 (20060101); B65D 75/36 (20060101); B65D
073/00 () |
Field of
Search: |
;206/363,438,461,467,469,471,523,524,45.14 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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|
|
|
|
|
|
1030845 |
|
May 1966 |
|
GB |
|
1580791 |
|
Dec 1980 |
|
GB |
|
Other References
Techform, Inc. "Custom Thermoforming" brochure Nov. 15, 1982. .
Packing Reference Issue, "Basic Thermoformed Card Pack
Constructions", 1986 vol. 31, No. 4, p. 134..
|
Primary Examiner: Fidei; David T.
Claims
What is claimed is:
1. A package for holding a product comprising
a body having a recess therein for receiving a product;
a foam insert disposed in said recess for holding the product
within said body;
a cover disposed over said body and completely covering said
recess;
flanges on said insert disposed laterally of said recess and
compressed between said body and said cover; and
a seal joining said cover to said body around said recess and to
said flanges, whereby said insert remains joined to said cover and
is removed with said cover when said cover is removed from said
body.
2. A package as recited in claim 1 wherein said body includes a
border disposed around said recess.
3. A package as recited in claim 2 wherein said insert is
configured as block and said flanges include a pair of flanges
extending laterally outwardly from said block and disposed between
said border and said cover.
4. A package as recited in claim 3 wherein said cover includes a
sheet extending over said border and said recess.
5. A package as recited in claim 4 wherein said cover compresses
said flanges between said borer and said sheet and said seal
includes a heat seal.
6. A package for holding at least one product comprising
a body having a depression therein for receiving at least one
product;
a solid block of foam material disposed in said depression for
securing the at least one product in said depression, said block
having a thickness;
a lid disposed over said body for covering said depression and said
block;
a rim on said body disposed around said depression; and
flanges of lesser thickness than said block extending from said
block and disposed between said rim and said lid, said lid being
continuously sealed to said flanges and said rim around said
depression.
7. A package as recited in claim 6 wherein said depression defines
an opening in said body and said rim is disposed around said
opening.
8. A package as recited in claim 7 wherein said lid extends over
said opening and said flanges when said lid is disposed over said
body.
9. A package as recited in claim 8 further including a seal sealing
said lid to said flanges and said rim.
10. A package as recited in claim 9 wherein said depression defines
a plurality of cavities for receiving the at least one product.
11. A package as recited in claim 10 wherein said cavities include
a central cavity and a pair of longitudinally aligned,
semi-cylindrical cavities extending outwardly from said central
cavity.
12. A package as recited in claim 11 wherein said body includes a
pair of side walls, a pair of end walls joining said side walls and
a connecting wall joining said side walls and said end walls
defining said central cavity and said block is disposed in said
central cavity in engagement with said side and end walls.
13. A package as recited in claim 12 wherein said block includes a
surface for supporting the at least one product thereon and said
lid urges said surface toward said connecting wall.
14. A package as recited in claim 13 wherein said surface positions
the at least one product in engagement with said connecting
wall.
15. A package as recited in claim 14 wherein said block is made
from foam in its entirety.
16. A package as recited in claim 15 wherein said block is made
from shrink-resistant, polyester urethane foam.
17. A package as recited in claim 9 wherein said flanges have
lengths extending along said rim and said seal bonds said flanges
to said lid continuously along said lengths.
18. A package as recited in claim 17 wherein said rim is made from
transparent material and said seal is viewable through said
rim.
19. A package as recited in claim 18 wherein said seal is
colored.
20. A package as recited in claim 19 wherein said body is formed as
a unitary, integral member of semi-rigid plastic.
21. A package as recited in claim 20 wherein said lid includes a
sheet of heat-bondable, flexible paper.
22. A package for holding a product comprising
a blister body defining a recess for receiving a product and a
border disposed around said recess;
a foam insert disposed in said recess to hold the product within
said body, said insert having a planar base with a pair of opposing
co-planar flanges extending outwardly from said base and overlying
said border; and
a cover sheet disposed over said base and heat sealed to said
border and said flanges continuously around said recess.
Description
BACKGROUND OF THE INVENTION
1. Field Of The Invention
The invention pertains to sealed packages and, more specifically,
to an improved, sealed blister package for securing products
therein prior to use and to a method for sealing products in a
blister package.
2. Description Of The Prior Art
Sealed blister containers for holding products have been proposed,
and such containers are useful for holding products, such as pre
sterilized medical devices, that must be isolated from the
environment prior to use due to the ability of the containers to be
hermetically sealed. Illustrative blister containers for holding
sterile medical devices are shown in U.S. Pat. Nos. 4,324,331 to
Ignasiak and 4,216,860 to Heimann and, generally, include an open,
relatively rigid blister tray having a peripheral flange and a
channel formed interiorly of the peripheral flange for receiving a
pre-sterilized medical device. One or more foam plugs are
positioned in the channel at discrete locations to hold distinct
parts of the medical device against the tray and inhibit movement
of the medical device within the container prior to use. A paper
backing sheet is positioned over the open tray in overlapping
engagement with the peripheral flange and the plugs and is
continuously sealed or bonded to the tray along the peripheral
flange to close the tray, maintain a sterile environment therein
and urge the plugs toward the parts of the medical device being
held against the tray. Additionally, the backing sheet is bonded
directly to the plugs to permit the container to be opened by
manually peeling away the backing sheet with the plugs attached
thereto, such that the medical device can be dropped freely from
the container onto a sterile field without manual contact with the
medical device itself. The sealing process typically involves
thermally compressing the backing sheet against the flange and
plugs to bond the backing sheet to the flange and plugs,
respectively. Because the plugs are located interiorly of the
peripheral flange at discrete locations, the backing sheet must be
compressed at multiple, distinct areas producing tensile stresses
in the paper backing sheet that could tear or weaken the backing
sheet. Furthermore, the foam plugs are contained entirely within
the peripheral confines of the channel and move downwardly in the
channel when the backing sheet is compressed against the plugs due
to the open cell characteristics of foam. Therefore, the backing
sheet must be compressed against the plugs with compressive forces
significantly greater than required to be exerted against the
relatively rigid peripheral flange to bond the backing sheet to the
plugs. The requirement for relatively high compressive forces
detracts from the efficiency of the sealing process and can produce
an unequal force distribution in the backing sheet resulting in
structural impairment thereof. Even when the required high
compressive forces are uniformly applied, the backing sheet
nonetheless frequently fails to bond to the plugs due to the plugs
being able to move considerably downwardly within the channel when
the backing sheet is compressed thereagainst, and the unbonded
plugs can drop onto the sterile field along with the medical device
when the backing sheet is peeled from the tray. Consequently,
conventional blister containers usually employ a coating on the
backing sheet to facilitate thermal bonding, and the coating must
be applied to the backing sheet at each of the distinct sealing
areas for the plugs. The need for thermal bonding facilitating
coatings significantly complicates the sealing process and commonly
fails to enhance bonding of the backing sheet to the plugs. Failure
of the backing sheet to bond to the plugs can not be visually
discerned because the interface of the backing sheet and the plugs
is concealed entirely from view by the backing sheet and the plugs,
respectively. Proper bonding of the backing sheet to the plugs is,
therefore, difficult to ascertain after the backing sheet has been
applied and has a negative impact on quality control.
A further drawback to conventional sealed blister containers is
that failure of the backing sheet to bond to the plugs allows the
plugs to move within the containers subsequent to the containers
being sealed along the peripheral flange. Accordingly, the plugs
are rendered ineffective in holding a medical device against the
tray, and the medical device can shift and move within the
container during shipping and handling prior to use. Movement of
the medical device within the container prior to use is undesirable
because the medical device can be damaged, and relatively fragile
medical devices are particularly likely to be compromised by such
movement. Prior art blister containers secure the plugs against
movement within the container by forming the tray with specially
configured walls adjacent the plugs to inhibit movement of the
plugs and, therefore, the medical device, within the channel.
Because different medical devices must be held by the plugs at
different points to effectively constrain the medical device
against movement within the channel, the trays must be highly
customized for specific medical devices to locate the walls in the
proper position for the plugs. Moreover, different sizes and
configurations of plugs are required for diverse medical devices,
and the walls must be specially configured in accordance with the
plugs being utilized. A single tray usually cannot be employed for
diverse medical devices and plugs, and conventional blister
containers are thusly limited. Additionally, the blister container
holding the medical device is frequently sterilized by gas or
radiation sterilization techniques after the backing sheet has been
sealed thereto; however, the plugs commonly shrink relative to the
walls during sterilization negating any benefits derived from the
walls in restricting movement of the plugs within the channel.
Another disadvantage of conventional blister containers is that the
plugs holding discrete parts of the medical device allows
unsupported parts of the medical device remote from the plugs to
move within the channel. Such movement is particularly likely when
the medical device is made from a flexible material and can
structurally impair the medical device.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to overcome
the aforementioned disadvantages of prior art sealed blister
packages and methods for sealing products in blister packages.
It is also an object of the present invention to provide a blister
package wherein a single seal bonds a cover sheet to the package
and to an insert positioned in the package for holding a product
therein.
A further object of the present invention is to enhance bonding
between a cover sheet of a blister package and a flexible,
compressible insert positioned in the package for securing a
product therein.
Moreover, it is an object of the present invention to provide a
blister package singly capable of receiving diverse sizes and
configurations of products and inserts for securing the products
against movement within the package.
Another object of the present invention is to provide a blister
package wherein movement of a compressible insert in the package is
prevented by securing the insert between a flange on the package
and a cover sheet secured to the flange.
An additional object of the present invention is to provide a
method for effectively and reliably sealing a cover sheet to a
blister package simultaneously with sealing of the cover sheet to a
compressible insert within the package along a single seal while
utilizing relatively low sealing forces.
Some of the advantages of the present invention are that the cover
sheet does not have to be bonded to the package at multiple,
discrete sealing areas, the need for bonding facilitating coatings
is eliminated, specially configured walls on the package for
preventing movement of the insert are not required, the sealing
force necessary to bond the cover sheet to the insert is reduced,
sealing forces are distributed equally across the cover sheet, the
insert holds a product by engaging the product over a substantial
portion of the length and width of the product, a single insert can
hold one or more products, the package can be sterilized after the
cover sheet has been bonded thereto without adversely affecting
securement of the insert against movement within the package and
bonding of the cover sheet to the insert can be visually
confirmed.
These and other objects, attributes and advantages are obtained
with the present invention as characterized by a blister package
including a peripheral flange around a central blister defining an
open cavity for receiving a product and a flexible, compressible
insert positionable in the cavity to hold and secure the product
against movement within the cavity. Opposing side flanges on the
insert extend laterally from the cavity over the peripheral flange,
and a cover sheet covering the cavity overlaps the peripheral
flange continuously around the central blister and tightly
compresses the side flanges against the peripheral flange to secure
the insert within the package. The cover sheet is bonded
continuously to the peripheral flange and to the side flanges along
a single peripheral seal permitting the cover sheet to be manually
peeled away from the peripheral flange while the side flanges
remain attached to the cover sheet to allow the product to be
dropped onto a sterile field without manual contact with the
product. According to the method of the present invention, the
peripheral flange is supported on a rigid support surface and the
cover sheet is positioned over the peripheral flange and the side
flanges to cover the open cavity. A heated sealing plate compresses
the cover sheet against the peripheral flange to compress the side
flanges between the cover sheet and the peripheral flange while
bonding the cover sheet to the peripheral flange simultaneously
with bonding of the side flanges to the cover sheet along a single
peripheral seal.
These and other objects and advantages of the present invention
will become apparent from the following description of the
preferred embodiment taken in conjunction with the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a sealed package according to the
present invention.
FIG. 2 is a broken, end sectional view of the sealed package of
FIG. 1 showing the lid being heat sealed to the insert and the
peripheral flange.
FIG. 3 is a side view of the sealed package of FIG. 1 showing the
insert remaining attached to the lid during opening of the
package.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in FIGS. 1 3, the package 10 of the present invention
includes a pre-formed, semi-rigid body 12 having a flat, or planar,
peripheral flange, rim or border 14 of generally uniform width and
thickness disposed around an open cavity or recess 15 defined by a
central blister or depression 16 in the body 12. The blister 16 is
sized and configured to hold one or more diverse products, such as
surgical screws, washers, tacks and the like, in the cavity 15, and
the size and configuration of the blister 16 can vary in accordance
with the product to be held. The blister 16, as shown by way of
example in FIGS. 1-3, includes a pair of spaced, generally parallel
side walls 18 joined generally perpendicularly to the peripheral
flange 14, a pair of generally parallel end walls 20 joined to the
side walls 18 and to the peripheral flange 14 and a wall 22 joining
the side walls 18 and end walls 20. The wall 22 includes a surface
24 generally parallel to the peripheral flange 14 extending
transversely between the side walls 18 centrally positioned
inwardly of the end walls 20 and semi-cylindrical walls 26 joined
to the surface 24 extending longitudinally therefrom to the end
walls 20. As shown in FIG. 2, semi-cylindrical walls 26 define in
end section arcs of circles having central longitudinal axes in
longitudinal alignment and disposed parallel to and centrally
between the side walls 18. The semi-cylindrical walls 26 are
tangential with the surface 24, and diametric lower ends 28 of the
semi-cylindrical walls 26 are joined to recessed surfaces 30
flanking the surface 24 and the lower ends 28 of the
semi-cylindrical walls 26 and joining the lower ends 28 to the side
walls 18 and the end walls 20. The recessed surfaces 30 are
positioned between the surface 24 and the flange 14, and shoulders
32 join the recessed surfaces 30 to the surface 24 and the side
walls 18 to the semi-cylindrical walls 26. Cavity 15 includes a
central recess 34 having a length measured between shoulders 32, a
width measured between side walls 18 and a depth measured between
flange 14 and surface 24, and a semi-cylindrical recess 36
bisecting the central recess 34 having a length measured between
the end walls 20, a maximum width measured between the recessed
ends 28 and a depth measured between recessed surfaces 30 and
surface 24. One or more products, such as a medical device or
surgical screw 38 can be positioned in the central recess 34
adjacent the surface 24, and a variety of size and configured
products can be singly or multiply received in the central recess
34. Additionally, relatively longitudinally elongated products
having a length greater than the length of the central recess 34
can be accommodated in the blister 16 via the relatively longer
length semi-cylindrical recess 36.
A flexible insert 40 for insertion in the cavity 15 to hold the
product 38 in engagement with the upper surface 24 and prevent
movement and dislocation of the product 38 within the package 10
prior to use includes a resilient block having spaced parallel
sides 42, parallel ends 44 joined to the sides 42, a planar, top 46
joined to the sides 42 and ends 44, a planar, base 48 generally
co-extensive in surface area with the top 46 joined to the sides 42
and ends 44, and side flanges or projections 50 of reduced depth or
thickness co-planar with the base 48 extending laterally outwardly
from the sides 42 continuously therealong. A cover sheet or lid 56
for closing the cavity 15 and sealing the product 38 and insert 40
in the body 12 includes a flexible sheet sized and configured to
completely cover the cavity 15 and to extend over the peripheral
flange 14 at least a small distance continuously around the cavity
15. As shown in FIGS. 1-3, the lid 56 is defined by a peripheral
edge 58 to be aligned with a peripheral edge 60 of the flange 14
when the lid 56 is positioned over the flange 14 covering the
cavity 15, and the peripheral flange 14 is notched to permit
corners 62 of the lid 56 to project independently outwardly from
the edge 60 of the peripheral flange 14 to facilitate grasping of
the lid 56 via the corners 62.
Preferably, the body 12 is made from a transparent material capable
of being formed or molded to define a semi-rigid peripheral flange
or border around a blister or depression defining a cavity for
receiving one or more products and an insert for securing the one
or more products in engagement with the body 12. A preferred
material for the body 12 is a semi-rigid plastic material, such as
polyvinyl chloride or the like, that can be vacuum or thermally
formed, maintain a hermetically sterile environment and is suitable
for heat sealing a lid thereto. The cavity 15 is preferably sized
to receive one or more products in the central recess 34 and is
preferably configured with cylindrical recess 36 to accommodate
relatively elongate products, although the cavity 15 can be sized
and configured in any selected manner in accordance with the one or
more products to be held. Preferably, the insert 40 is fabricated
from a flexible, compressible material that deforms around the
product being held and thereby urges the product into engagement
with the surface 24. A preferred material for the insert 40 is 2.0
P.C.F. polyester urethane foam that resists shrinkage when gas or
radiation sterilized and has a cell count of approximately 38-44
cells/inch. The height, or depth, of the insert 40 as measured
between the top 46 and the base 48 is selected to permit the top 46
to urge the product 38 against the upper surface 24 of the body 12
when the inert 40 is positioned in the central recess 34 with the
side flanges 50 overlapping the peripheral flange 14 on the body
12. Preferably, the length of the insert 40 as measured between the
ends 44 and the width of the insert 40 as measured between the
sides 42 are selected to allow the insert 40 to substantially fill
the volume of the central recess 34 and permit the top 46 to engage
one or more products over a substantial portion of the length and
width of the one or more products facing the insert 40. The side
flanges 50 extend laterally outwardly from the sides 42 of the
insert 40 a short distance and, according to one embodiment for the
insert 40, the side flanges 50 are approximately 1/8" deep and
extend from the sides 42 approximately 3/16" continuously along the
length of the insert 40. The lid 56 is preferably made from a
material capable of being heat sealed or bonded to the body 12 and
the insert 40 by thermal compression, and a preferred material is
spun-bonded polyolefin membrane or the like, such as TYVEK, which
produces a colored interface between the peripheral flange 14 and
the lid 56 when the lid 56 is thermally bonded thereto. The lid 56
is sized and configured to cover the cavity 15 in its entirety and
the peripheral flange 14 continuously around the cavity 15; and,
preferably, the lid 56 is sized and configured to have the
peripheral edge 58 capable of being substantially aligned in
overlapping fashion with the peripheral edge 60 on the flange
14.
In order to produce a sealed package in accordance with the present
invention, as shown in FIG. 2, the body 12 is placed in a support
64 having a female cavity 66 therein for receiving the blister 16
and a rigid, planar support surface 68 surrounding the female
cavity 66 for supporting the peripheral flange 14 thereon when the
blister 16 is placed in the female cavity 66. A product, such as
the surgical screw 38, is placed in the central recess 34 and
opposing ends of the product can project into one or both opposing
ends of the semi-cylindrical recess 36. The insert 40 is positioned
over the product 38 in the central recess 34 such that the insert
40 substantially fills the central recess 34, the side flanges 50
overlap and are supported on the peripheral flange 14 and the top
46 of the insert 40 deforms around the product 38 and engages a
substantial portion of the length and width of the product 38
facing the top 46. The lid 56 is placed over the body 12 to cover
the cavity 15 in its entirety, to extend over the peripheral flange
14 continuously around the cavity 15 and to align the peripheral
edge 58 on the lid 56 with the peripheral edge 60 on the flange 14.
A heated sealing plate 70 sized and configured to cover the lid 56
is pressed vertically downwardly against the lid 56 to apply
compressive sealing forces thereto in a direction normal to the
support surface 68. Sealing plate 70 compresses the lid 56 against
the peripheral flange 14 while simultaneously compressing the side
flanges 50 between the lid 56 and the peripheral flange 14. Heat
and pressure applied by the sealing plate 70 bonds the lid 56 to
the peripheral flange 14 continuously along the interface of the
lid 56 and the peripheral flange 14 to produce a colored peripheral
seal 72 disposed continuously around the blister 16, and the lid 56
is simultaneously bonded to the side flanges 50 along sealing areas
74, shown in FIG. 2, contained within the peripheral seal 72. In
other words, the lid 56 is bonded to both the peripheral flange 14
and the side flanges 50 of the insert 40 along a single peripheral
seal 72 without the need for multiple, discrete sealing areas
interiorly of the peripheral flange 14 that could impose tensile
stress on the lid 56 and result in damage to and weakening of the
lid. The seal 72 is viewable through the flange 14 due to the body
12 being made of transparent material and permits visual inspection
and confirmation of proper bonding of the lid 56 to the peripheral
flange 14 and the side flanges 50. The side flanges 50 are bonded
to the lid 56 reliably and effectively because the relatively small
depth of the side flanges 50 is readily compressed between the lid
56 and the relatively rigid flange 14 as further rigidified by the
support surface 64, and the need for bonding facilitating coatings
is eliminated. Relatively less compressive force is required to
bond the side flanges 50 to the lid 56 than would be required to
bond other parts of the insert 40, such as the base 48, to the lid
56 because the base 48 is movable considerably downwardly within
the central recess 34 when the insert 40 is compressed over its
full depth or height. The base 48 of the insert 40 need not be
bonded to the lid 56, and the sealing force required to be applied
by the sealing plate 70 to bond the lid 56 to the insert 40 is
reduced. Furthermore, the reduced sealing force is applied
uniformly, or equally, across the lid 56 maintaining the structural
integrity of the lid. The side flanges 50 being retained between
the peripheral flange 14 and the lid 56 and being bonded to the lid
56 at sealing areas 74 prevent movement of the insert 40 and,
therefore, dislocation of the product 38, within the package 10
without the need for specially configured movement restricting
walls in blister 16. Additionally, the blister 16 can singularly
accept a variety of inserts and products for sealing therein.
After sealing of the lid 56 thereto, the package 10 can be
sterilized utilizing gas or radiation sterilization techniques. The
insert 40 will not shrink as a result of the sterilization process,
and the peripheral seal 72 maintains a sterile environment within
the package 10 and prevents the insert 40 from moving or becoming
detached from the lid 56 during shipping and handling of the
package 10 prior to use. The lid 56 urges the top 46 of the insert
40 toward the surface 24, and the product 38 is positioned by the
top 46 to engage the surface 24 and prevent dislocation of the
product 38 within the package 10. Furthermore, the top 46 of the
insert 40 supports a substantial portion of the length and width of
the product 38 facing the insert 40 and inhibits movement or
shifting of unsupported parts of the product. The package 10 is
opened by manually grasping the corners 62 on the lid 56 and
manually peeling the lid 56 away from the body 12 to break the
peripheral seal 72. As the lid 56 is pulled away from the body 12,
the insert 40 remains solidly attached to the lid 56 at sealing
areas 74, and the product 38 can be freely dropped onto a sterile
field, as shown in FIG. 3, without manually contacting the product
38 and without the insert 40 falling onto the sterile field.
Having described a preferred embodiment of a new and improved
blister package and method for sealing products in a blister
package, it is believed that other modifications, variations and
changes will be suggested to those skilled in the art in view of
the teachings set forth herein. It is therefore to be understood
that all such variations, modifications and changes are believed to
fall with the scope of the present invention as defined by the
appended claims.
* * * * *